diff --git a/src/App.css b/src/App.css
index 373a9e0..9694611 100644
--- a/src/App.css
+++ b/src/App.css
@@ -1,4 +1,9 @@
+*, :before, :after {
+  box-sizing: inherit;
+}
+
 :root {
+  box-sizing: border-box;
   font-family: Inter, Avenir, Helvetica, Arial, sans-serif;
   font-size: 16px;
   line-height: 24px;
@@ -76,6 +81,22 @@
   margin: 0 auto;
 }
 
+.puzzle-header {
+  display: flex;
+  flex-direction: row;
+  > h1 {
+    flex-grow: 1;
+    text-align: left;
+    margin: 0;
+  }
+}
+
+.puzzle-header-actions {
+  display: flex;
+  flex-direction: row;
+  gap: calc(1 * var(--unit));
+}
+
 .puzzle-row {
   display: flex;
   justify-content: center;
@@ -149,6 +170,13 @@
   min-width: calc(20 * var(--unit));
 }
 
+select {
+  font-size: 0.8em;
+  line-height: 1;
+  margin: 0;
+  padding: 1em;
+}
+
 a {
   font-weight: 500;
   color: #646cff;
diff --git a/src/App.tsx b/src/App.tsx
index b07defe..8df8ac6 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,118 +1,58 @@
 import { For } from "solid-js";
-import connections from "./assets/connections.json";
 import "./App.css";
-import { shuffleArray } from "./utils";
-import { createStore } from "solid-js/store";
-
-type Connection = (typeof connections)[number];
-type Answer = Connection["answers"][number];
-
-function fromIndex(index: number): [number, number] {
-  const col = index % 4;
-  const row = (index - col) / 4;
-  return [row, col];
-}
+import useAppModel from "./useAppModel";
 
 function App() {
-  const [store, setStore] = createStore({
-    puzzleIndex: 0,
-    pinnedCount: 3,
-    selected: [] as number[],
-    solvedGroups: [] as Answer[],
-    puzzle: shuffleArray(Array.from({ length: 16 }, (_, i) => i)),
-    get answers() {
-      return connections[store.puzzleIndex].answers;
-    },
-  });
-
-  const getFromPuzzle = (index: number) => {
-    const puzzleIndex = store.puzzle[index];
-    const [groupIndex, memberIndex] = fromIndex(puzzleIndex);
-    const group = store.answers[groupIndex];
-    return {
-      group: group.group,
-      level: group.level,
-      answer: store.answers[groupIndex].members[memberIndex],
-    };
-  };
-
-  const handleGuess = () => {
-    const selectedAnswers = store.selected.map((x) => getFromPuzzle(x));
-    const { level } = selectedAnswers[0];
-    const isCorrect = selectedAnswers.every((x) => x.level === level);
-    if (!isCorrect) {
-      // TODO you got it wrong
-      alert("wrong");
-      return;
-    }
-    const selectedPinnedCount = store.selected.reduce(
-      (acc, cur) => acc + (cur < store.pinnedCount ? 1 : 0),
-      0
-    );
-    setStore({
-      pinnedCount: store.pinnedCount - selectedPinnedCount,
-      puzzle: store.puzzle.filter((x) =>
-        store.selected.every((s) => store.puzzle[s] !== x)
-      ),
-      selected: [],
-    });
-    const newSolvedGroup = store.answers.find((x) => x.level === level);
-    if (newSolvedGroup != null) {
-      setStore({
-        solvedGroups: [...store.solvedGroups, newSolvedGroup],
-      });
-    }
-    if (store.puzzle.length === 0) {
-      // completely solved!
-    }
-  };
-
-  const handleShuffle = () => {
-    const pinned = store.puzzle.slice(0, store.pinnedCount);
-    const toShuffle = store.puzzle.slice(store.pinnedCount);
-    setStore({
-      puzzle: [...pinned, ...shuffleArray(toShuffle)],
-    });
-  };
-
-  const handlePinUnpin = () => {
-    if (store.selected.every((x) => x < store.pinnedCount)) {
-      // we are unpinning
-      const puzzleStart = Array.from({ length: store.pinnedCount }, (_, i) => i)
-        .filter((x) => !store.selected.includes(x))
-        .map((x) => store.puzzle[x]);
-      const puzzleMiddle = store.selected.map((x) => store.puzzle[x]);
-      const puzzleEnd = store.puzzle.slice(store.pinnedCount);
-      const newPuzzle = [...puzzleStart, ...puzzleMiddle, ...puzzleEnd];
-      setStore({
-        pinnedCount: store.pinnedCount - store.selected.length,
-        selected: [],
-        puzzle: newPuzzle,
-      });
-      return;
-    }
-    // we are pinning
-    const puzzleStart = store.puzzle.slice(0, store.pinnedCount);
-    const puzzleMid = store.selected
-      .filter((x) => x >= store.pinnedCount)
-      .map((x) => store.puzzle[x]);
-    const puzzleEnd = Array.from(
-      { length: 16 - store.pinnedCount },
-      (_, i) => i + store.pinnedCount
-    )
-      .filter((x) => !store.selected.includes(x))
-      .map((x) => store.puzzle[x]);
-    setStore({
-      pinnedCount: puzzleStart.length + puzzleMid.length,
-      selected: [],
-      puzzle: [...puzzleStart, ...puzzleMid, ...puzzleEnd]
-    })
-  };
+  const {
+    connections,
+    store,
+    setStore,
+    handleGuess,
+    handlePinUnpin,
+    handleSelectGame,
+    handleShuffle,
+    getFromPuzzle,
+  } = useAppModel();
 
   return (
     <main class="container">
-      <h1>Slick Connections</h1>
       <div class="puzzle">
+        <header class="puzzle-header">
+          <h1>Slick Connections</h1>
+          <div class="puzzle-header-actions">
+            <button
+              type="button"
+              on:click={() => {
+                handleSelectGame(store.puzzleId - 1);
+              }}
+              disabled={store.puzzleId === 1}
+            >
+              -
+            </button>
+            <select
+              name="puzzleNumber"
+              id="puzzleNumber"
+              on:input={({ target: { value } }) =>
+                handleSelectGame(parseInt(value, 10))
+              }
+            >
+              <For each={connections}>
+                {({ id }) => <option value={id}>{id}</option>}
+              </For>
+            </select>
+            <button
+              type="button"
+              on:click={() => {
+                handleSelectGame(store.puzzleId + 1);
+              }}
+              disabled={
+                store.puzzleId === connections[connections.length - 1].id
+              }
+            >
+              +
+            </button>
+          </div>
+        </header>
         <For each={store.solvedGroups}>
           {({ group, level, members }) => (
             <div class="puzzle-row">
diff --git a/src/useAppModel.ts b/src/useAppModel.ts
new file mode 100644
index 0000000..56724e6
--- /dev/null
+++ b/src/useAppModel.ts
@@ -0,0 +1,130 @@
+import connections from "./assets/connections.json";
+import { shuffleArray } from "./utils";
+import { createStore } from "solid-js/store";
+
+type Connection = (typeof connections)[number];
+type Answer = Connection["answers"][number];
+
+function fromIndex(index: number): [number, number] {
+  const col = index % 4;
+  const row = (index - col) / 4;
+  return [row, col];
+}
+
+export default function useAppModel() {
+  const [store, setStore] = createStore({
+    puzzleId: 1,
+    pinnedCount: 0,
+    selected: [] as number[],
+    solvedGroups: [] as Answer[],
+    puzzle: shuffleArray(Array.from({ length: 16 }, (_, i) => i)),
+    get answers() {
+      return connections.find((x) => x.id === store.puzzleId)!.answers;
+    },
+  });
+
+  const handleSelectGame = (newId: number) => {
+    setStore({
+      puzzleId: newId,
+      selected: [],
+      pinnedCount: 0,
+      puzzle: shuffleArray(Array.from({ length: 16 }, (_, i) => i)),
+      solvedGroups: [],
+    });
+  };
+
+  const getFromPuzzle = (index: number) => {
+    const puzzleIndex = store.puzzle[index];
+    const [groupIndex, memberIndex] = fromIndex(puzzleIndex);
+    const group = store.answers[groupIndex];
+    return {
+      group: group.group,
+      level: group.level,
+      answer: store.answers[groupIndex].members[memberIndex],
+    };
+  };
+
+  const handleGuess = () => {
+    const selectedAnswers = store.selected.map((x) => getFromPuzzle(x));
+    const { level } = selectedAnswers[0];
+    const isCorrect = selectedAnswers.every((x) => x.level === level);
+    if (!isCorrect) {
+      // TODO you got it wrong
+      alert("wrong");
+      return;
+    }
+    const selectedPinnedCount = store.selected.reduce(
+      (acc, cur) => acc + (cur < store.pinnedCount ? 1 : 0),
+      0
+    );
+    setStore({
+      pinnedCount: store.pinnedCount - selectedPinnedCount,
+      puzzle: store.puzzle.filter((x) =>
+        store.selected.every((s) => store.puzzle[s] !== x)
+      ),
+      selected: [],
+    });
+    const newSolvedGroup = store.answers.find((x) => x.level === level);
+    if (newSolvedGroup != null) {
+      setStore({
+        solvedGroups: [...store.solvedGroups, newSolvedGroup],
+      });
+    }
+    if (store.puzzle.length === 0) {
+      // completely solved!
+    }
+  };
+
+  const handleShuffle = () => {
+    const pinned = store.puzzle.slice(0, store.pinnedCount);
+    const toShuffle = store.puzzle.slice(store.pinnedCount);
+    setStore({
+      puzzle: [...pinned, ...shuffleArray(toShuffle)],
+    });
+  };
+
+  const handlePinUnpin = () => {
+    if (store.selected.every((x) => x < store.pinnedCount)) {
+      // we are unpinning
+      const puzzleStart = Array.from({ length: store.pinnedCount }, (_, i) => i)
+        .filter((x) => !store.selected.includes(x))
+        .map((x) => store.puzzle[x]);
+      const puzzleMiddle = store.selected.map((x) => store.puzzle[x]);
+      const puzzleEnd = store.puzzle.slice(store.pinnedCount);
+      const newPuzzle = [...puzzleStart, ...puzzleMiddle, ...puzzleEnd];
+      setStore({
+        pinnedCount: store.pinnedCount - store.selected.length,
+        selected: [],
+        puzzle: newPuzzle,
+      });
+      return;
+    }
+    // we are pinning
+    const puzzleStart = store.puzzle.slice(0, store.pinnedCount);
+    const puzzleMid = store.selected
+      .filter((x) => x >= store.pinnedCount)
+      .map((x) => store.puzzle[x]);
+    const puzzleEnd = Array.from(
+      { length: 16 - store.pinnedCount },
+      (_, i) => i + store.pinnedCount
+    )
+      .filter((x) => !store.selected.includes(x))
+      .map((x) => store.puzzle[x]);
+    setStore({
+      pinnedCount: puzzleStart.length + puzzleMid.length,
+      selected: [],
+      puzzle: [...puzzleStart, ...puzzleMid, ...puzzleEnd],
+    });
+  };
+
+  return {
+    connections,
+    store,
+    setStore,
+    handleGuess,
+    handlePinUnpin,
+    handleSelectGame,
+    handleShuffle,
+    getFromPuzzle,
+  };
+}